Aditya L1 Mission Update

 **Aditya L1 Mission - Final Good Bye to Earth 19 Sept**.: Early hours of 19 Sept around 2am. **ISRO scientists* will execute a maneuver/operation called **Trans-Lagragean Point 1 Insertion (𝐓𝐋𝟏𝐈)**. With this Aditya L1 will start its journey towards L1 point.Thus **finally leaving** the orbit around Earth.

**All the Best Team ISRO and Aditya L1**


15 JULY 2023 UPDATE : 

Source : Times of India / ISRO 

15 July 2023 EBN : The operation, which was carried out to increase the spacecraft's apogee (farthest point from Earth) began at around 12.05pm as planned and lasted for 11-and-a-half minutes, multiple scientists confirmed to STOI.

After Saturday's maneuver, "Spacecraft is now in 41762km x 173km orbit," said Isro.

Minor Burn on 16 July 2023 If all goes as planned, scientists will carry out a minor burning of onboard propulsion systems on Sunday 16 July to increase the perigee (closest point to Earth). It will be pushed to about 220km from the current position.  "The perigee will then remain stable. The remaining three manoeuvres we've planned will all be for apogee raising," another scientist said.

The three other operations around Earth, as reported by TOI earlier, are planned for July 18, 20 and 25 to push apogee to around 1-lakh-km before Isro attempts to slingshot the spacecraft towards Moon, in the intervening night of July 31 and August 1.


On 14th July 2023 another historic space exploration mission to moon was launched by Indian Space Research Organisation (ISRO) from SHAR, Sriharikota. Chandrayaan-3 is a follow-up lunar exploration mission by ISRO after Chandrayaan-2 and it would reattempt a soft-landing near lunar south-pole (69.37°S, 32.35°E) on 23 or 24 August 2023. Chandrayaan-3 composite consists of a propulsion module, lander 'Vikram' and rover 'Pragyan' and cumulatively they have 6 science payloads and a laser retroreflector on them.

Speaking to reporters after the successful launch, ISRO Chairman S. Somanath said the next 42 days are crucial. “As per the nominal programme, we will have five earth-bound manoeuvres [that] will end on July 31. After that we have the trans-lunar insertion, [which] will take place on August 1. After that, it will be captured [by the] moon.This will be followed by the separation of the propulsion module and the lander module on August 17. “The landing is currently planned on August 23 at 5.47 pm IST, if everything goes as per plan,” he added.

Hailing the launch, Prime Minister Narendra Modi tweeted: “Chandrayaan-3 scripts a new chapter in India’s space odyssey. It soars high, elevating the dreams and ambitions of every Indian... This momentous achievement is a testament to our scientists’ relentless dedication. I salute their spirit and ingenuity!”

Minister of State Jitendra Singh, who was present at the launch, said, “It is indeed a moment of glory for India. Thank you team ISRO for making India proud... Today is also a day of vindication: vindication of the dream Vikram Sarabhai [had] six decades ago.”



In the coming months various historic mission are being planned to launched from our country in coming months/years. On one hand, India is sending a mission to the moon, and other hand sending a mission to Sun. At the same time, India is preparing for Gaganyaan Mission to take our own astronauts to space.

Hence, on eve of India’s third Mission to Moon  Chandrayaan 3 launch on 14 July 2023 Planetary Society of India is starting 75 days unique campaign called “To the Moon and Beyond”. Beginning with Chandrayaan 3 regular updates of the journey of the mission to moon will be shared on daily basis. Importantly awareness sessions in Schools, Colleges will be organized during period of this campaign.

Invitation to Schools/Colleges to Host: Educational institutions in both telugu states and across India can contact us at 799 348 2012 for hosting the sessions.  In this regard Veteran Senior Scientist C. Ramakrishna Retd. ISRO has released the poster at the meet. 


Before we discussion overall specification. Here is the gist of several advanced technologies which are present in Lander such as,

  1. Altimeters: Laser & RF based Altimeters
  2. Velocimeters: Laser Doppler Velocimeter & Lander Horizontal Velocity Camera
  3. Inertial Measurement: Laser Gyro based Inertial referencing and Accelerometer package
  4. Propulsion System: 800N Throttleable Liquid Engines, 58N attitude thrusters & Throttleable Engine Control Electronics
  5. Navigation, Guidance & Control (NGC): Powered Descent Trajectory design and associate software elements
  6. Hazard Detection and Avoidance: Lander Hazard Detection & Avoidance Camera and Processing Algorithm
  7. Landing Leg Mechanism.

Preparation : To demonstrate the above said advanced technologies in earth condition, several Lander special tests have been planned and carried out successfully viz.

  1. Integrated Cold Test - For the demonstration of Integrated Sensors & Navigation performance test using helicopter as test platform
  2. Integrated Hot test – For the demonstration of closed loop performance test with sensors, actuators and NGC using Tower crane as test platform
  3. Lander Leg mechanism performance test on a lunar simulant test bed simulating different touch down conditions.

The overall specifications for Chandrayaan-3 is provided below:

Sl No.ParameterSpecifications
1.Mission Life (Lander & Rover)One lunar day (~14 Earth days)
2.Landing Site (Prime)4 km x 2.4 km 69.367621 S, 32.348126 E
3.Science PayloadsLander:
  1. Radio Anatomy of Moon Bound Hypersensitive ionosphere and Atmosphere (RAMBHA)
  2. Chandra’s Surface Thermo physical Experiment (ChaSTE)
  3. Instrument for Lunar Seismic Activity (ILSA)
  4. Laser Retroreflector Array (LRA) Rover:
  5. Alpha Particle X-Ray Spectrometer (APXS)
  6. Laser Induced Breakdown Spectroscope (LIBS) Propulsion Module:
  7. Spectro-polarimetry of HAbitable Planet Earth (SHAPE)
4.Two Module Configuration
  1. Propulsion Module (Carries Lander from launch injection to Lunar orbit)
  2. Lander Module (Rover is accommodated inside the Lander)
  1. Propulsion Module: 2148 kg
  2. Lander Module: 1752 kg including Rover of 26 kg
  3. Total: 3900 kg
6.Power generation
  1. Propulsion Module: 758 W
  2. Lander Module: 738W, WS with Bias
  3. Rover: 50W
  1. Propulsion Module: Communicates with IDSN
  2. Lander Module: Communicates with IDSN and Rover. Chandrayaan-2 Orbiter is also planned for contingency link.
  3. Rover: Communicates only with Lander.
8.Lander Sensors
  1. Laser Inertial Referencing and Accelerometer Package (LIRAP)
  2. Ka-Band Altimeter (KaRA)
  3. Lander Position Detection Camera (LPDC)
  4. LHDAC (Lander Hazard Detection & Avoidance Camera)
  5. Laser Altimeter (LASA)
  6. Laser Doppler Velocimeter (LDV)
  7. Lander Horizontal Velocity Camera (LHVC)
  8. Micro Star sensor
  9. Inclinometer & Touchdown sensors
9.Lander ActuatorsReaction wheels – 4 nos (10 Nms & 0.1 Nm)
10.Lander Propulsion SystemBi-Propellant Propulsion System (MMH + MON3), 4 nos. of 800 N Throttleable engines & 8 nos. of 58 N; Throttleable Engine Control Electronics
11.Lander Mechanisms
  1. Lander leg
  2. Rover Ramp (Primary & Secondary)
  3. Rover
  4. ILSA, Rambha & Chaste Payloads
  5. Umbilical connector Protection Mechanism,
  6. X- Band Antenna
12.Lander Touchdown specifications
  1. Vertical velocity: ≤ 2 m / sec
  2. Horizontal velocity: ≤ 0.5 m / sec
  3. Slope: ≤ 120


Chandrayaan-3 is scheduled to launch on 14 July 2023 at 2.35pm. It is a follow-on mission to Chandrayaan-2 to demonstrate end-to-end capability in safe landing and roving on the lunar surface. It consists of Lander and Rover configuration. It will be launched by LVM3 from SDSC SHAR, Sriharikota. The propulsion module will carry the lander and rover configuration till 100 km lunar orbit. The propulsion module has Spectro-polarimetry of Habitable Planet Earth (SHAPE) payload to study the spectral and Polari metric measurements of Earth from the lunar orbit.

Lander payloads: Chandra’s Surface Thermophysical Experiment (ChaSTE) to measure the thermal conductivity and temperature; Instrument for Lunar Seismic Activity (ILSA) for measuring the seismicity around the landing site; Langmuir Probe (LP) to estimate the plasma density and its variations. A passive Laser Retroreflector Array from NASA is accommodated for lunar laser ranging studies.

Rover payloads: Alpha Particle X-ray Spectrometer (APXS) and Laser Induced Breakdown Spectroscope (LIBS) for deriving the elemental composition in the vicinity of landing site.

Chandrayaan-3 consists of an indigenous Lander module (LM), Propulsion module (PM) and a Rover with an objective of developing and demonstrating new technologies required for Inter planetary missions. The Lander will have the capability to soft land at a specified lunar site and deploy the Rover which will carry out in-situ chemical analysis of the lunar surface during the course of its mobility. The Lander and the Rover have scientific payloads to carry out experiments on the lunar surface. The main function of PM is to carry the LM from launch vehicle injection till final lunar 100 km circular polar orbit and separate the LM from PM. Apart from this, the Propulsion Module also has one scientific payload as a value addition which will be operated post separation of Lander Module. The launcher identified for Chandrayaan-3 is GSLV-Mk3 which will place the integrated module in an Elliptic Parking Orbit (EPO) of size ~170 x 36500 km.

The mission objectives of Chandrayaan-3 are:

  1. To demonstrate Safe and Soft Landing on Lunar Surface
  2. To demonstrate Rover roving on the moon and
  3. To conduct in-situ scientific experiments.


 On 9th May 2023 one of the interesting celestial events “Zero Shadow” will occur at 12.12 pm Noon. Hence to create awareness about this occurrence promoting astronomy, the role of the tropics in Earth's climate is celebrated as “Zero Shadow Day”.  

Zero Shadow occurs when Sun is exactly overhead for a location. Whereas this event occurs twice every year.  The date of Occurrence of this event varies according to the observer’s location in certain latitudes on the Globe.  The next Zero Shadow for Hyderabad will occur on 3rd August 2023 (12.22 pm Noon).

Its a fact that Earth taken has a globe, is separated into two halves by an imaginary line of the Equator. In which northern halve is called the northern hemisphere and the southern halve is called Southern Hemisphere. Importantly for various purposes, we have lines of latitude and longitude drawn on the Earth’s Globe.  Wherein the latitude of the “Tropic of Cancer” is located 23.5 degrees North of the Equator. Whereas the Latitude of the “Tropic of Capricorn” is located 23.5 Degree South of the Equator.  It is important to know 40% of the world's population inhabits the tropical regions of the globe. These regions are typically characterized by hot and humid climates, abundant rainfall, and lush vegetation.

Zero Shadow occurs when Sun reaches the highest point in the sky above the Tropic of Cancer or Tropic of Capricorn every year. Rotation of Earth with 23.5 Degree axial tilt and Earth’s Elliptic path of revolution around the Sun. Results in North Ward movement of the Sun (Uttarayana) or South Ward Movement of Sun (Dakshinayana) in the earth Sky thus contributing to the occurrence of Zero Shadow Day.  Dates and timings.



10 May 2023 (11.53 a.m.)

2 August 2023 (12.04pm Noon)


11 May 2023 (12.08 pm Noon)

1 August (12.18 pm Noon)


12 May 2023 (11.52am)

31 July (12.03 pm Noon)


12 May 2023 (11.51am)

31 July (12.01 pm Noon)